Justification:
There is little information on the population of this species. It occurs only on the Hawaiian islands and is restricted to streams below the first precipitous waterfall (that the larval Eleotris cannot navigate). It appears to be able to survive in urbanized Oahu. Further research is required on population and threats.It is listed as Data Deficient.

Corkum (2002) found this species in densities of 1.5 fish per m2 in a tidally influenced pond in Hilo, Hawaii.Postlarvae have been collected in streams during most months of the year, with by far the greatest numbers caught during March (Fitzsimons and Nishimoto 1991).

This species inhabits coastal streams and does not climb steep waterfalls (Murphy and Cowan 2007). Post-larval recruits tend to migrate upstream on a rising tide just after dark (Eleotris in general are more active at night).Sim (unpublished MSc thesis, 2006) stated that the species occurs on all main islands and was abundant on Oahu, feeding on fishes (including small Eleotris sandwicensis), crustaceans and aquatic snails. Fecundity in females was 5,000 to 55,000 eggs, with ripe individuals being found throughout the year; gonosomatic index was highest in both sexes from June 2004 through February 2005.

Decline in suitable habitat (and damage to riparian vegetation) is an immediate threat due to the isolation of the Hawaiian chain, with water management an additional potential threat. However, it seems that Eleotris sandwicensis may be tolerant of large variations in environmental conditions (Luton et al. 2007), even in Oahu where large-scale clearing and urbanization has occurred.